We've known it was coming for several months, and now it's here: the Office 365 E5 corporate plan, which replaces the current E4 plan. Office 365 E5 ups its capabilities as well as its price -- and how. An E4 plan costs $22 per user per month, whereas its E5 replacement costs $35 per user per month -- a 59 percent jump. That's probably more than most enterprises are willing to bear, despite the feature updates.

You'll have to choose by June 2016, when the E4 plan goes away and enterprises are forced to move to either the $20-per-user-per-month E3 plan or the $35-per-user-per-month E5 plan.

What does Office 365 E5 add that makes Microsoft thinks enterprises will pony up 59 percent more from their current E4 plan?

What you get from Office 365 E5

E5 includes everything in the E4 plan: Unlimited email, all the social tools (Yammer, SharePoint Online, Office 365 video), the Office suite (including Access for Windows users), and OneDrive for Business.

But the E5 plan also includes several features that cost extra for E4 (and E3): Advanced Threat Protection for secure attachments and URLs, Cloud PBX, PSTN Conferencing, PSTN Calling, Delve Analytics, and Power BI Pro. Microsoft has a handy chart (scroll down that page to see it) showing what each plan includes.

On the techie side, there's a lot of buzz around Delve Analytics, which lets users perform organizational analytics, so they can see most commonly used data, co-worker interactions, and key trends. Power BI Pro lets users analyze the data in Office 365 through dashboards.

Of the newer features, I believe the most intriguing are the cloud-based call management (aka PSTN calling), Skype Meeting Broadcast, and PSTN conferencing.

Skype Meeting Broadcast lets you host an online meeting or webinar for as many as 10,000 people. Real-time polling, sentiment tracking, and Yammer messaging are built in, so you can gain feedback during the meeting and make it more of an interactive discussion.

Cloud-based call management, done through Skype for Business, lets you combine PSTN calling with your cloud PBX. Thus, you can make and receive traditional phone calls, as well as perform normal call actions like hold, resume, forward, and transfer. PSTN conferencing lets people join meetings via voice even if there is no Internet connection, by using a cellular or landline call instead.

For anyone who has had to set up and configure servers to provide BI, to perform analytics, to set up a unified messaging environment with an existing PSTN and PBX environment, the Office 365 E5 plan is awesome because it saves you from configuring, managing, and maintaining the server infrastructure on the back end. Doing this via the cloud makes it much easier for a business to move to more-intelligent corporate communication and collaboration.

Running the numbers to get the right Office 365 plan mix

Still, the E5 plan is a mega license and provides more than the average worker would ever use or need. If you use many of these add-on capabilities in the E4 plan, you may find that the E5 plan is no more expensive and perhaps even cheaper. If you don't need those new features, then the E5 plan's cost will be hard to swallow.

However, keep in mind, it's not an all-or-nothing licensing model. You can purchase E1 for some users, E3 for other users, and E5 for those users who need all it provides.

You can also buy add-ons to the E3 license for some of the features included in the E5 plan -- bolting them onto an E3 plan can cost less than moving to the E5 plan if you only want some of the E5 features. Some people criticize the add-on approach as "muddy licensing" that makes management and budgeting much more confusing. But I believe it's the only way to give each user exactly what they want and/or need.

It's like McDonald's: If you want the Quarter Pounder Meal, choose number 3. Want to supersize it? Pay a bit more. Want extra fries or a chocolate shake? Add that to your order. You're not locked in; you can order what you want or need.

Yes, it may be easier to choose a plan and run with it, but when you need some but not all added features, the add-on approach is best. And if you find that the add-ons' total price is the same as or more than the E5 plan, then buy the E5 plan.

J. Peter Bruzzese is a six-time-awarded Microsoft MVP, currently for Office Servers and Services and previously for Exchange/Office 365. He is a technical speaker and author with more than a dozen books sold internationally. He's the co-founder of ClipTraining, the creator of ConversationalGeek.com, instructor on Exchange/Office 365 video content for Pluralsight, and a consultant for Mimecast and others.